Cellular cushion

ABSTRACT

A cellular cushioning system includes cells or support units arranged in one or more stacked arrays. The cells are hollow chambers that resist deflection due to compressive forces, similar to compression springs. The arrays are attached to one or more intermedial binding layers. The intermedial binding layer(s) links the cells together while allowing the cells to deform independently of one another. An external load compresses of one of the void cells within an independent compression range without significantly compressing at least one void cell adjacent the compressed void cell. The independent compression range is the displacement range of the compressed void cell that does not significantly affect the compression of adjacent void cells. If the void cell is compressed beyond the independent compression range, the intermedial binding layers may be deflected and/or the void cells adjacent the compressed void cell may be compressed.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims benefit of priority to U.S. ProvisionalPatent Application No. 61/558,564, entitled “Cellular Cushion” and filedon Nov. 11, 2011, which is specifically incorporated by reference hereinfor all that it discloses or teaches. In addition, the presentapplication is a continuation of U.S. application Ser. No. 13/674,293entitled “Cellular Cushion,” and filed on Nov. 12, 2012, which is alsospecifically incorporated by reference herein for all that it disclosesor teaches.

BACKGROUND

Cushioning systems are used in a wide variety of applications includingcomfort and impact protection of the human body. A cushioning system isplaced adjacent a portion of the body and provides a barrier between thebody and one or more objects that would otherwise impinge on the body.For example, a pocketed spring mattress contains an array ofclose-coupled metal springs that cushion the body from a bed frame.Similarly, chairs, gloves, knee-pads, helmets, etc. may each include acushioning system that provides a barrier between a portion of the bodyand one or more objects.

A variety of structures are used for cushioning systems. For example, anarray of close-coupled closed-cell air and/or water chambers oftenconstitute air and water mattresses. An array of close-coupled springsoften constitutes a conventional mattress. Further examples include openor closed cell foam and elastomeric honeycomb structures. For cushioningsystems utilizing an array of closed or open cells or springs, eitherthe cells or springs are directly coupled together or one or moreunifying layers are used to couple each of the cells or springs togetherat their extremities. While directly coupling the cells or springstogether or indirectly coupling the extremities of the cells or springstogether is effective in tying the cushioning system together, theindependence of each of the cells or springs is reduced. This lack ofindependence can lead to an increased load being placed on a small areaof the body (referred to herein as a point load). A point load deformingone of the cells or springs is likely to deform adjacent cells orsprings directly or by stressing the unifying layer(s). As a result, theresistance to deflection at the point of contact increases due to thedeflection of multiple cells or springs. The increased resistance todeflection may cause pressure points on portions of a user's body thatprotrude into the cushioning system more than other portions of theuser's body (e.g., at a user's shoulders and hips on a mattress).

SUMMARY

Implementations described and claimed herein address the foregoingproblems by decoupling individual void cells in a cellular cushioningsystem and allowing the void cells to deform independently of oneanother, within an independent deformation range. This reduces thepotential for pressure points on a user's body. Further, the void cellsdeform independently under loads oriented in multiple directions, withinthe independent deformation range.

The presently disclosed technology further addresses the foregoingproblems by compressing a void cell in a matrix of void cells coupledtogether with an intermedial binding layer in a direction normal to theintermedial binding layer without substantially compressing at least oneadjacent void cell, wherein the void cell is compressed within anindependent compression range of the void cell.

The presently disclosed technology still further addresses the foregoingproblems by providing an apparatus for interfacing a body with an objectcomprising a first matrix of void cells and an intermedial binding layercoupling at least two of the void cells in the first matrix of voidcells, wherein compression of a void cell in a direction normal to theintermedial binding layer occurs without substantial deflection of atleast one adjacent void cell, wherein compression of the void cell iswithin an independent compression range of the void cell.

The presently disclosed technology further yet addresses the foregoingproblems by providing a method of manufacturing a cellular cushioningsystem comprising molding a first matrix of void cells open toward andinterconnected by a first intermedial binding layer; molding a secondmatrix of void cells open toward and interconnected by a secondintermedial binding layer; and laminating the first and secondintermedial binding layers together so that openings in the void cellsof the first and second intermedial binding layers face one another,wherein compression of a void cell in a direction normal to theintermedial binding layer occurs without substantial deflection of atleast one adjacent void cell, and wherein compression of the void cellis within an independent compression range of the void cell.

Other implementations are also described and recited herein.

BRIEF DESCRIPTIONS OF THE DRAWINGS

FIG. 1 illustrates a user lying on an example cellular cushioningsystem.

FIG. 2 illustrates a perspective view of an example cellular cushioningsystem.

FIG. 3 illustrates an elevation view of an example cellular cushioningsystem in an unloaded state.

FIG. 4 illustrates an elevation view of an example offset cellularcushioning system in an unloaded state.

FIG. 5 illustrates an elevation view of an example stacked cellularcushioning system 500 in an unloaded state.

FIG. 6 illustrates an elevation view of an example cellular cushioningsystem in a partially loaded state.

FIG. 7 illustrates an elevation view of an example cellular cushioningsystem in a fully loaded state.

FIG. 8 illustrates a perspective view of an example cellular cushioningsystem with a pixilated layer.

FIG. 9 illustrates an elevation view of an example cellular cushioningsystem with a pixilated layer in an unloaded state.

FIG. 10 illustrates an elevation view of an example cellular cushioningsystem with a pixilated layer in a partially loaded state.

FIG. 11 illustrates an elevation view of an example cellular cushioningsystem with a pixilated layer in a fully loaded state.

FIG. 12 illustrates a perspective view of an example curved cellularcushioning system.

FIG. 13 illustrates a displacement over force graph for neighboring voidcells in an example cellular cushioning system.

FIG. 14 illustrates a displacement over force graph for opposing voidcells in an example cellular cushioning system.

FIG. 15 illustrates a pressure over displacement graph for two examplecellular cushioning systems compared to three other cushioning systems.

FIG. 16 illustrates a kneepad incorporating an example cellularcushioning system.

FIG. 17 illustrates example operations for manufacturing and using acellular cushioning system.

DETAILED DESCRIPTIONS

FIG. 1 illustrates a user 102 lying on an example cellular cushioningsystem 100. The cellular cushioning system 100 includes void cells(e.g., void cell 104) or support units arranged in a top matrix 106 (orarray) and a bottom matrix 108 (or array). The cellular cushioningsystem 100 is depicted on a frame 103. Some implementations will notinclude the frame 103. The void cells are hollow chambers that resistdeflection due to compressive forces, similar to compression springs.The top matrix 106 is attached to a top surface of a central orintermedial binding layer 110 and the bottom matrix 108 is attached to abottom surface of the intermedial binding layer 110. The intermedialbinding layer 110 links the void cells together while allowing the voidcells to compress independently of one another, at least within anindependent compression range of the void cells (discussed in moredetail with regard to FIG. 13).

In one implementation, each of the void cells are individually attachedto the intermedial binding layer 110 and not to each other. Further,each of the void cells within the top matrix 106 or bottom matrix 108are individually compressible under load without compression of adjacent(i.e., neighboring, opposing, and/or neighbor opposing) void cells,within the independent compression range of the void cells. Outside ofthe independent compression range, compression of an individual voidcell causes adjacent void cells to compress via deflection of theintermedial binding layer 110. For example, void cells forming the topmatrix 106 under the neck, lower back, and knees of the user 102 areindividually compressed and distribute the weight of the user 102 evenlyover those areas. However, void cells under the upper back and buttocksof the user 102 are compressed sufficiently to cause the intermedialbinding layer 110 to deflect, which in turn causes void cells in thebottom matrix 108 to compress. Deflection of the intermedial bindinglayer 110 also causes adjacent void cells in the top matrix 106 todeflect and adjacent void cells in the bottom matrix 108 to compress.

Each of the void cells creates a relatively constant force to resistdeflection. In one implementation, the void cells in the bottom matrix108 have a higher resistance to deflection that the void cells in thetop matrix 106. As a result, in less compressed areas (e.g., the user'sneck, lower back, and knees), only void cells in the top matrix 106 areengaged and the user's weight is distributed evenly over contact of theuser 102 with the cellular cushioning system 100. In more compressedareas (e.g., the user's upper back and buttocks), the user experiencesincreased pressure because the user's weight is sufficient toadditionally deflect the intermedial binding layer 110 and thus engagethe void cells in the bottom matrix 108. In another implementation,resistance to deflection of the individual void cells within the topand/or bottom matrices are varied according to expected loading of thecellular cushioning system 100. For example, void cells located near theuser's upper back and buttocks may be stiffer than void cells locatednear the user's neck, lower back, and knees.

In one implementation, an optional pixilation layer (see e.g., FIGS.8-11) is attached to extremities of the top matrix 106 and/or the bottommatrix 108 opposite the intermedial binding layer 110. The pixilationlayer provides a substantially planar surface on the top or bottom ofthe cellular cushioning system 100 to aid in comfort or cleanlinessconcerns and yet sill allows for substantially independent compressionof individual void cells, for example. The pixilation layer is discussedin more detail with regard to FIGS. 8-11.

FIG. 2 illustrates a perspective view of an example cellular cushioningsystem 200. The cellular cushioning system 200 includes void cells(e.g., void cell 204) arranged in a top matrix 206 and a bottom matrix208. The void cells are hollow chambers that resist deflection due tocompressive forces, similar to compression springs. However, unlikecompression springs, deflection of the void cells does not yield alinear increase in resistive force. Instead, the resistive force todeflection of the void cells is relatively constant for the majority ofthe void cell's compression displacement. This allows the cellularcushioning system 200 to conform to a user's body with an even force onthe user's body. In other implementations, each of the void cells mayhave a positive or negative spring rate. Further, the spring rate ofeach of the void cells may vary depending upon the void cell's relativeposition within the cellular cushioning system 200.

At least the material, wall thickness, size, and shape of each of thevoid cells define the resistive force each of the void cells can apply.Materials used for the void cells are generally elastically deformableunder expected load conditions and will withstand numerous deformationswithout fracturing or suffering other breakdown impairing the functionof the cellular cushioning system 200. Example materials includethermoplastic urethane, thermoplastic elatomers, styrenic co-polymers,rubber, Dow Pellethane®, Lubrizol Estane®, Dupont™ Hytrel®, ATOFINAPebax®, and Krayton polymers. Further, the wall thickness may range from5 mil to 80 mil. Still further, the size of each of the void cells mayrange from 5 mm to 70 mm sides in a cubical implementation. Further yet,the void cells may be cubical, pyramidal, hemispherical, or any othershape capable of having a hollow interior volume. Other shapes may havesimilar dimensions as the aforementioned cubical implementation. Stillfurther, the void cells may be spaced a variety of distances from oneanother. An example spacing range is 2.5 mm to 150 mm.

In one implementation, the void cells have a square base shape, with atrapezoidal volume and a rounded top. That void cell geometry mayprovide a smooth compression profile of the system 200 and minimalbunching of the individual void cells. Bunching occurs particularly oncorners and vertical sidewalls of the void cells where the materialbuckles in such a way as to create multiple folds of material that cancause pressure points and a less uniform feel to the cellular cushioningsystem overall. Still further, rounded tops of the void cells mayenhance user comfort and the spacing of the individual void cells maycreate a user feel similar to convoluted foam.

In another implementation, the void cells have a round base shape, witha cylindrical-shaped volume and a rounded top. That void cell geometrymay also provide a smooth compression profile of a cellular cushioningsystem and minimal bunching of the individual void cells. Still further,the rounded tops may enhance user comfort and the closer spacing of theindividual void cells (as compared to the void cells of FIG. 13) maycreate a more uniform feel to a user. Other void cell shapes arecontemplated herein.

The material, wall thickness, cell size, and/or cell spacing of thecells within the cellular cushioning system 200 may be optimized tominimize generation of mechanical noise by compression (e.g., bucklingof the side walls) of the void cells. For example, properties of thecells may be optimized to provide a smooth relationship betweendisplacement and an applied force (see e.g., FIGS. 13 and 14). Further,a light lubricating coating (e.g., talcum powder or oil) may be used onthe exterior of the void cells to reduce or eliminate noise generated byvoid cells contacting and moving relative to one another. Reduction orelimination of mechanical noise may make use of the cellular cushioningsystem 200 more pleasurable to the user. Still further, geometry of thetop of the void cells may be smooth to enhance user comfort.

The top matrix 206 is attached to a top surface of a central orintermedial binding layer 210 and the bottom matrix 208 is attached to abottom surface of the intermedial binding layer 210. The intermedialbinding layer 210 links the void cells together while allowing the voidcells in the top matrix 206 to deform independently of one another, atleast to an extent. The intermedial binding layer 210 may be constructedwith the same potential materials as the void cells and in oneimplementation is contiguous with the void cells. In the cellularcushioning system 200, the void cells in the top matrix 206 align withthe void cells in the bottom matrix 208.

In other implementations, the void cells in the top matrix 206 are notaligned with the void cells in the bottom matrix 208 (see e.g., FIG. 4).In yet other implementations, the void cells in the top matrix 206 are asubstantially different size and/or shape than the void cells in thebottom matrix 208. Further still, one or more coupling ribs (not shown)may be attached to the exterior of the void cells extending verticallyto the intermedial binding layer 210. These ribs can add additionalstiffness to the void cells, but may in some implementations affect theindependency of the void cells.

Each void cell is surrounded by neighboring void cells within a matrix.For example, void cell 204 is surrounded by three neighboring void cells205 within the top matrix 206. In cellular cushioning system 200, thereare three neighboring void cells for each corner void cell, fiveneighboring void cells for each edge cell, and eight neighboring voidcells for the rest of the void cells. Other implementations may havegreater or fewer neighboring void cells for each void cell. Further,each void cell has a corresponding opposing void cell within an oppositematrix. For example, void cell 204 in the top matrix 206 is opposed byvoid cell 207 in the bottom matrix 208. Other implementations do notinclude opposing void cells for some or all of the void cells. Stillfurther, each void cell has corresponding neighbor opposing cells withinan opposite matrix. For example, void cell 204 in the top matrix 206 hascorresponding neighbor opposing cells 209 in the bottom matrix 208. Theneighbor opposing cells are opposing void cells for each neighboringvoid cell of a particular void cell.

The neighboring void cells, opposing void cells, and neighbor opposingvoid cells are collectively referred to herein as adjacent void cells.In various implementations, one or more of the neighboring void cells,opposing void cells, and opposing neighbor void cells are notsubstantially compressed within an independent compression range of anindividual void cell.

In one implementation, the void cells are filled with ambient air. Inanother implementation, the void cells are filled with a foam or a fluidother than air. The foam or certain fluids may be used to insulate auser's body, facilitate heat transfer from the user's body to/from thecellular cushioning system 200, and/or affect the resistance todeflection of the cellular cushioning system 200. In a vacuum ornear-vacuum environment (e.g., outer space), the hollow chambers may beun-filled.

Further, the void cells may have one or more holes (e.g., hole 211)through which air or other fluid may pass freely when the void cells arecompressed and de-compressed. By not relying on air pressure forresistance to deflection, the void cells can achieve a relativelyconstant resistance force to deformation. Still further, the void cellsmay be open to one (i.e., fluidly connected) another via passages (e.g.,passage 213) through the intermedial binding layer 210. The holes and/orpassages may also be used to circulate fluid for heating or coolingpurposes. For example, the holes and/or passages may define a paththrough the cellular cushioning system 200 in which a heating or coolingfluid enters the cellular cushioning system 200, follows a path throughthe cellular cushioning system 200, and exits the cellular cushioningsystem 200. The holes and/or passages may also control the rate at whichair may enter, move within, and/or exit the cellular cushioning system200. For example, for heavy loads that are applied quickly, the holesand/or passages may restrict how fast air may exit or move within thecellular cushioning system 200, thereby providing additional cushioningto the user.

The holes may be placed on a top of a void cell and a bottom of anopposing void cell on the cellular cushioning system 200 to facilitatecleaning. More specifically, water and/or air could be forced throughthe holes in the opposing void cells to flush out contaminants. In animplementation where each of the void cells are connected via passages,water and/or air could be introduced at one end of the cellularcushioning system 200 and flushed laterally through the cellularcushioning system 200 to the opposite end to flush out contaminants.Further, the cellular cushioning system 200 could be treated with ananti-microbial substance or the cellular cushioning system 200 materialitself may be anti-microbial.

The cellular cushioning system 200 may be manufactured using a varietyof manufacturing processes (e.g., blow molding, thermoforming,extrusion, injection molding, laminating, etc.). In one implementation,the system 200 is manufactured in two halves, a first half comprises thetop matrix 206 attached to an upper half of the intermedial bindinglayer 210. The second half comprises the bottom matrix 208 attached to alower half of the intermedial binding layer 210. The two halves of theintermedial binding layer 210 are then laminated, glued, or otherwiseattached together with the top matrix 206 and the bottom matrix 208 onopposite sides of the intermedial binding layer 210. In oneimplementation, the two halves of the intermedial binding layer 210 areperiodically bonded together, leaving a gap between the two halves ofthe intermedial binding layer 210 that fluidly connects the void cellsin one or both of the top matrix 206 and the bottom matrix 208.

Further, each of the void cells in the two halves may be open or closedat its interface with the intermedial binding layer 210. As a result,when the two halves are joined, opposing void cells on the top matrix206 and bottom matrix 208 may be either open or closed to each other. Inanother implementation, the cellular cushioning system 200 ismanufactured in one piece rather than two pieces as discussed above.Further, a cellular cushioning system 200 according to the presentlydisclosed technology may include more than two matrices of void cellsstacked on top of one another (e.g., two or more cellular cushioningsystems 200 stacked on top of one another).

FIG. 3 illustrates an elevation view of an example cellular cushioningsystem 300 in an unloaded state. The cellular cushioning system 300includes void cells (e.g., void cell 304) arranged in a top matrix 306and a bottom matrix 308. The top matrix 306 is attached to a top surfaceof a central or intermedial binding layer 310 and the bottom matrix 308is attached to a bottom surface of the intermedial binding layer 310.The intermedial binding layer 310 links the void cells together whileallowing the void cells to deform independently of one another, at leastwithin an independent compression range of the void cells.

In one implementation, the thickness of each of the void cells variesover a height of the void cell. For example, near bottom 316 of voidcell 304, the wall thickness may be greater than near top 318 of voidcell 304, or vice versa. This phenomenon may be a by-product of themanufacturing process or may be intentionally designed into themanufacturing process. Regardless, varying the thickness of the voidcells over their height can be used to yield a changing resistive forcedepending upon the amount of compression of the void cells (i.e.,yielding a positive and/or increasing spring rate).

In another implementation, the height of the void cells in the bottommatrix 308 is different than the height of the void cells in the topmatrix 306. In yet another implementation, the size and shape of thevoid cells in the top matrix 306 differ substantially than that in thebottom matrix 308. The void cells in the top matrix 306 maysubstantially collapse into the void cells in the bottom matrix 308under compression, or vice versa. In other implementations, void cellsin the top matrix 306 and the bottom matrix 308 may be offset such thatthey are only partially opposing or not opposing (see e.g., FIG. 4).

FIG. 4 illustrates an elevation view of an example offset cellularcushioning system 400 in an unloaded state. The cellular cushioningsystem 400 includes void cells (e.g., void cell 404) arranged in a topmatrix 406 and a bottom matrix 408. The void cells in the top matrix 406are offset from those in the bottom matrix 408 such that each void cellin a matrix overlaps 2 or more opposing void cells. The top matrix 406is attached to a top surface of a central or intermedial binding layer410 and the bottom matrix 408 is attached to a bottom surface of theintermedial binding layer 410. The intermedial binding layer 410 linksthe void cells together while allowing the void cells to deformindependently of one another, at least within an independent compressionrange of the void cells.

For example, void cell 404 in the top matrix 406 overlaps void cells428, 430 in the bottom matrix 408 (i.e., 1:2 overlapping). In someimplementations, the void cell 404 in the top matrix 406 also overlaps 2additional void cells in the bottom matrix 408 extending into thedepicted illustration (i.e., 1:4 overlapping). If void cell 404 iscompresses, it will deform substantially independently within anindependent compression range of the void cell 404. Outside of theindependent compression range of the void cell 404, compression of thesystem 400 will largely engage void cells 428, 430 and to a lesserextent, neighboring void cells via the intermedial binding layer 410.Further, the overlapping cells provide fluid passageways between thevoid cell in the top matrix 406 and the bottom matrix 408. This allowsair or other fluid within a compressed void to enter and exit the voidcell freely or substantially freely. In other implementations, one voidcell in the top matrix 406 may overlap any number of void cells in thebottom matrix 408 (e.g., 1:3 overlapping, 1:6 overlapping, etc.).

FIG. 5 illustrates an elevation view of an example stacked cellularcushioning system 500 in an unloaded state. The cellular cushioningsystem 500 includes void cells (e.g., void cells 503, 504) stackedwithin one another. Stacking void cells within one another increases theresistance to deflection of the combined stacked void cell. In oneimplementation, void cell 503 is smaller than void cell 504 to allow abetter fit. Further, the void cells are arranged in a top matrix 506 anda bottom matrix 508. The top matrix 506 is attached to a top surface ofa central or intermedial binding layer 510 and the bottom matrix 508 isattached to a bottom surface of the intermedial binding layer 510. Theintermedial binding layer 510 links the void cells together whileallowing the void cells to deform independently of one another, at leastwithin an independent compression range of the void cells.

FIG. 6 illustrates an elevation view of an example cellular cushioningsystem 600 in a partially loaded state. The cellular cushioning system600 includes void cells (e.g., void cell 604) arranged in a top matrix606 and a bottom matrix 608. The top matrix 606 is attached to a topsurface of a central or intermedial binding layer 610 and the bottommatrix 608 is attached to a bottom surface of the intermedial bindinglayer 610. The intermedial binding layer 610 links the void cellstogether while allowing the void cells to deform independently of oneanother, at least within an independent compression range of the voidcells.

A load is applied to the void cell 604 using a test apparatus 620. Thevoid cell 604 compresses vertically without substantially affectingneighboring void cells (e.g., void cells 622, 624) in the top matrix606. Further, an opposing void cell 626 in the bottom matrix 608 andneighboring opposing void cells 628, 630 are deflected very littlebecause the intermedial binding layer 610 distributes the point loadapplied to the void cell 604 to multiple void cells within the bottommatrix 608. Further, the void cells within the bottom matrix 608 mayhave more or less resistance to compression than the cells in the topmatrix 606 to provide a desired relationship between displacement and anapplied force (see e.g., FIGS. 13 and 14). If the load were applied to agroup of void cells as opposed to the single void cell 604, the group ofvoid cells would be compressed and adjacent void cells to the group ofvoid cells would remain relatively uncompressed. This relationship isreferred to herein as decoupling the void cells from one another. Thedecoupling is only applicable up to a threshold based on an independentcompression range, as illustrated by FIG. 7.

FIG. 7 illustrates an elevation view of an example cellular cushioningsystem 700 in a fully loaded state. The cellular cushioning system 700includes void cells (e.g., void cell 704) arranged in a top matrix 706and a bottom matrix 708. The top matrix 706 is attached to a top surfaceof a central or intermedial binding layer 710 and the bottom matrix 708is attached to a bottom surface of the intermedial binding layer 710.The intermedial binding layer 710 links the void cells together whileallowing the void cells to deform independently of one another, at leastwithin an independent compression range of the void cells.

Similar to that shown in FIG. 6, a load is applied to the void cell 704using a test apparatus 720. The test apparatus 720 is applying a greaterforce than test apparatus 620 of FIG. 6, and is compressing the cellularcushioning system 700 further. Void cell 704 is fully compressed andopposing void cell 726 is nearly, if not fully compressed. Since theintermedial binding layer 710 is engaged once the void cell 704 iscompressed beyond an independent compression threshold, opposing voidcell 726 is compressed and neighbor opposing void cells (e.g., voidcells 728, 730) are partially compressed via the intermedial bindinglayer 710. Further, neighbor void cells (e.g., void cells 722, 724) aredeflected, but not substantially compressed, by compression of void cell704. By engaging adjacent void cells, this yields a higher resistance tocompression as the cellular cushioning system 700 nears a fullydeflected state.

FIG. 8 illustrates a perspective view of an example cellular cushioningsystem 800 with a pixilated layer 832. The cellular cushioning system800 includes void cells (e.g., void cell 804) arranged in a top matrix806 and a bottom matrix 808. The top matrix 806 is attached to a topsurface of a central or intermedial binding layer 810 and the bottommatrix 808 is attached to a bottom surface of the intermedial bindinglayer 810. The intermedial binding layer 810 links the void cellstogether while allowing the void cells of the top matrix 806 to deformindependently of one another, at least within an independent compressionrange of the void cells.

The pixilated layer 832 is a thin sheet of material affixed to upperextremities of each of the void cells in the top matrix 806. In otherimplementations, the pixilated layer 832 is affixed to lower extremitiesof each of the void cells in the bottom matrix 808. The pixilated layer832 may be made of similar materials as the void cells and intermedialbinding layer 810. The thickness of the pixilated layer 832 may varyaccording to desired flexibility and durability, for example. Thepixilated layer 832 is flat on top of each void cell and has grooves(e.g., groove 834) between each of the void cells. The grooves helpmaintain independent compression of each of the void cells from adjacentvoid cells, at least within an independent compression range of the voidcells. The groove depth and width may be tailored for an intendedindependent compression range of the void cells.

FIG. 9 illustrates an elevation view of an example cellular cushioningsystem 900 with a pixilated layer 932 in an unloaded state. The cellularcushioning system 900 includes void cells (e.g., void cell 904) arrangedin a top matrix 906 and a bottom matrix 908. The top matrix 906 isattached to a top surface of a central or intermedial binding layer 910and the bottom matrix 908 is attached to a bottom surface of theintermedial binding layer 910. The intermedial binding layer 910 linksthe void cells together while allowing the void cells to deformindependently of one another, at least within an independent compressionrange of the void cells. The pixilated layer 932 is a thin sheet ofmaterial affixed to upper extremities of each of the void cells in thetop matrix 906. The pixilated layer 932 is flat on top of each void celland has grooves (e.g., groove 934) between each of the void cells.

FIG. 10 illustrates an elevation view of an example cellular cushioningsystem 1000 with a pixilated layer 1032 in a partially loaded state. Thecellular cushioning system 1000 includes void cells (e.g., void cell1004) arranged in a top matrix 1006 and a bottom matrix 1008. The topmatrix 1006 is attached to a top surface of a central or intermedialbinding layer 1010 and the bottom matrix 1008 is attached to a bottomsurface of the intermedial binding layer 1010. The intermedial bindinglayer 1010 links the void cells together while allowing the void cellsto deform independently of one another, at least within an independentcompression range of the void cells. The pixilated layer 1032 is a thinsheet of material affixed to upper extremities of each of the void cellsin the top matrix 1006. The pixilated layer 1032 is flat on top of eachvoid cell and has grooves (e.g., groove 1034) between each of the voidcells.

A load is applied to the void cell 1004 using a test apparatus 1020. Thevoid cell 1004 compresses vertically without substantially affectingneighboring void cells (e.g., void cells 1022, 1024) in the top matrix1006. While void cells 1004, 1022, 1024 are connected with the pixilatedlayer 1032, grooves 1034, 1036 spread open or otherwise distort to helpprevent deflection of void cell 1004 from substantially affecting theneighboring void cells. Further, an opposing void cell 1026 in thebottom matrix 1008 is deflected very little because it has a higherresistance to compression than cell 1004 and load is distributed viabinding layer 1010. If the load were applied to a group of void cells asopposed to the single void cell 1004, the group of void cells would becompressed and void cells adjacent to the compressed group of void cellswould remain relatively uncompressed. This relationship is referred toherein as decoupling the void cells from one another. The decoupling isonly applicable up to a predetermined deflection, as illustrated by FIG.11.

FIG. 11 illustrates an elevation view of an example cellular cushioningsystem 1100 with a pixilated layer 1132 in a fully loaded state. Thecellular cushioning system 1100 includes void cells (e.g., void cell1104) arranged in a top matrix 1106 and a bottom matrix 1108. The topmatrix 1106 is attached to a top surface of a central or intermedialbinding layer 1110 and the bottom matrix 1108 is attached to a bottomsurface of the intermedial binding layer 1110. The intermedial bindinglayer 1110 links the void cells together while allowing the void cellsto deform independently of one another, at least within an independentcompression range of the void cells. The pixilated layer 1132 is a thinsheet of material affixed to upper extremities of each of the void cellsin the top matrix 1106. The pixilated layer 1132 is flat on top of eachvoid cell and has grooves (e.g., groove 1134) between each of the voidcells.

Similar to that shown in FIG. 10, a load is applied to the void cell1104 using a test apparatus 1120. The test apparatus 1120 is applying agreater force than test apparatus 1020 of FIG. 10, and is compressingthe cellular cushioning system 1100 further. Void cell 1104 is fullycompressed and opposing void cell 1126 is nearly, if not fullycompressed. While void cells 1104, 1122, 1124 are connected with thepixilated layer 1132, grooves 1134, 1136 unfold and prevent deflectionof the void cell 1104 from fully engaging the neighboring void cells,even in a fully deflected state. Since the intermedial binding layer1110 is engaged once the void cell 1126 is compressed, neighbor opposingvoid cells in the bottom matrix 1108 are partially compressed bycompression of void cell 1104. The depth and width of the grooves withinthe pixilated layer 1132 affects to what degree deflection of a voidcell affects adjacent void cells. By engaging adjacent void cells, thisyields a higher resistance to compression as the cellular cushioningsystem 1100 nears a fully deflected state.

FIG. 12 illustrates a perspective view of an example curved cellularcushioning system 1200. The cellular cushioning system 1200 includesvoid cells (e.g., void cell 1204) arranged in a top matrix 1206 and abottom matrix 1208. The top matrix 1206 is attached to a top surface ofa central or intermedial binding layer 1210 and the bottom matrix 1208is attached to a bottom surface of the intermedial binding layer 1210.The intermedial binding layer 1210 links the void cells together whileallowing the void cells to deform independently of one another, at leastwithin an independent compression range of the void cells.

The cellular cushioning system 1200 may be applied over a curved surface1253 (e.g., an interior of a helmet). Because the intermedial bindinglayer 1210 is located between the top matrix 1206 and bottom matrix 1208of void cells, the intermedial binding layer 1210 does not restrict thecellular cushioning system 1200 to planar applications. The cellularcushioning system 1200 may be manipulated to conform to any surface thatis to be cushioned from contact with a user's body. Even when thecellular cushioning system 1200 is manipulated to conform to a curvedsurface, the void cells are still oriented substantially perpendicularto the curved surface. This ensures consistent resistance to compressionfrom the void cells.

FIG. 13 illustrates a displacement over force graph 1300 for neighboringvoid cells in an example cellular cushioning system. The graph 1300illustrates the relationship between force and displacement of a loadedvoid cell (dotted line 1310) versus the relationship between force anddisplacement of neighboring void cells (solid line 1320). At lowerforces (e.g., at approximately 0.0-2.5 lbs.), the loaded void cell iscompressed significantly with little change in force (i.e., non-springlike behavior or non-compliant with Hooke's Law), at least within anindependent compression range of the void cells. As the void cellbecomes nearly fully compressed, it takes an increasing amount of forceto continue to compress the loaded void cell (e.g., at approximately2.5-7.5 lbs). When the void cell is nearly fully compressed, it takes arelatively large increase of force to compress the void cell arelatively small additional amount (e.g., approximately 7.5-17.5 lbs).

At smaller compression displacements of the loaded void cell (e.g.,0.0-1.5 in), neighboring void cells are not significantly compressed(e.g., illustrated by independent compression range 1338. As the loadedvoid cell becomes more compressed (e.g., 1.5-2.7 in), however, theneighboring void cells experience some compression. In oneimplementation, this is due to deformation of a central or intermedialbinding layer and/or pixilated layer associated with both the loadedvoid cell and the neighboring void cells. However, the relativemagnitude of the compression of the neighboring void cells as comparedto the loaded void cell remains relatively small (in one implementation,a maximum of approximately 20%). As a result, even under fully or nearlyfully loaded conditions, the neighboring void cells in the cellularcushioning system remain mostly independent.

FIG. 14 illustrates a displacement over force graph 1400 for opposingvoid cells in an example cellular cushioning system. The graph 1400illustrates the relationship between force and displacement of a voidcell in a top matrix of void cells (solid line 1410) versus therelationship between force and displacement of an opposing void cell ina bottom matrix of void cells (dotted line 1420). At lower forces (e.g.,at approximately 0.0-5.0 lbs.), the force/displacement relationship ofeach of the opposing void cells is substantially linear and equal. Aboveapproximately 5.0 lbs., but below approximately 30.0 lbs., the top voidcell achieves substantial deflection before the bottom void cell. Above30.0 lbs., the force/displacement relationship of each of the opposingvoid cells is again substantially linear and equal.

In other implementations, the void cell in the top matrix of void cellswill have an independent compression range within which the opposingvoid cell in the bottom matrix of void cells is substantiallyuncompressed, similar to the relationship between neighboring void cellsas illustrated in FIG. 13.

FIG. 15 illustrates a pressure over displacement graph 1500 for twoexample cellular cushioning systems compared to three other cushioningsystems. The graph 1500 illustrates the relationship between pressureapplied to the cushioning systems and compressive displacement of thecushioning systems. Line 1510 represents a first example thermoplasticelastomer cellular cushioning system with 0.5″ wide, tall, and deepsquare void cells. Further, the void cells are aligned and opposing eachother with a 25 mil wall thickness. Line 1520 represents a secondexample cellular cushioning system with 0.5″ wide, tall, and deep flattop square void cells. The void cells are offset and opposing each otherwith a 25 mil wall thickness. Line 1530 represents a 2.0″ thickreticulated urethane comfort foam used in mattress applications andlines 1540 and 1550 each represent a convoluted comfort foam mattresstopper.

Lines 1510 and 1520, which represent cellular cushioning systems, asdisclosed herein illustrate that a relatively low pressure is requiredto cause displacement (e.g., from 0 to about 0.4 inches) of the cellularcushioning systems as compared to the foam illustrated by line 1530).This may enhance user comfort under lower load conditions. Further,under higher load conditions (e.g., from about 0.4 to about 0.8 inches),lines 1510 and 1520 illustrate that the cellular cushioning systemsexhibit a relatively high pressure required to cause additionaldisplacement of the cellular cushioning systems as compared to all threefoams (lines 1530, 1540, and 1550). As a result, the cellular cushioningsystems are able to offer a user greater support under higher loadconditions than any the foam systems and better comfort to the userunder low load conditions than at least one of the foam systems.

FIG. 16 illustrates a kneepad 1600 incorporating an example cellularcushioning system 1605. The cellular cushioning system 1605 includesvoid cells (e.g., void cell 1604) or support units arranged in a topmatrix and a bottom matrix (not shown). The cellular cushioning system1600 is depicted conforming to a curved inner surface of the kneepad1600. In various implementations, the kneepad 1600 is rigid, semi-rigid,or flexible, depending on the purpose of the kneepad 1600. The topmatrix is attached to a top surface of a central or intermedial bindinglayer 1610 and the bottom matrix is attached to a bottom surface of theintermedial binding layer 1610. The intermedial binding layer 1610 linksthe void cells together while allowing the void cells to compressindependently of one another, at least within an independent compressionrange of the void cells (as discussed in detail above).

In one implementation, each of the void cells are individually attachedto the intermedial binding layer 1610 and not to each other. Further,each of the void cells within the top matrix are individuallycompressible under load without compression of adjacent (i.e.,neighboring, opposing, and/or neighbor opposing) void cells, within theindependent compression range of the void cells. Outside of theindependent compression range, compression of an individual void cellcauses adjacent void cells to compress via deflection of the intermedialbinding layer 1610. For example, void cells forming the top matrixconform to the surface contour of a user's knee and individuallycompress and distribute a load on the user's knee evenly over thoseareas.

Each of the void cells creates a relatively constant force to resistdeflection. In one implementation, the void cells in the bottom matrixhave a higher resistance to deflection that the void cells in the topmatrix. As a result, in less highly loaded areas (e.g., sides of theuser's knees), only void cells in the top matrix are engaged and theuser's weight is distributed evenly over contact of the user with thecellular cushioning system 1605. In more compressed areas (e.g., thecenter of the user's knees), the user experiences increased pressurebecause the user's weight is sufficient to additionally deflect theintermedial binding layer 1610 and thus engage the void cells in thebottom matrix. Resistance to deflection of the individual void cellswithin the top and/or bottom matrices may be varied according toexpected loading of the kneepad 1600.

FIG. 17 illustrates example operations 1700 for manufacturing and usinga cellular cushioning system. A first molding operation 1705 molds afirst matrix of void cells interconnected by a first planar intermedialbinding layer. A second molding operation 1710 molds a second matrix ofvoid cells interconnected by a second planar intermedial binding layer.The intermedial binding layers may have openings at each of the voidcells. In another implementation, the matrices of void cells are formedsimultaneously from a sheet of material using a blow molding tube (e.g.,parison tube). In yet other implementation, the first matrix of voidcells and second matrix of void cells are interconnected by singularplanar intermedial binding layer.

A bonding operation 1715 bonds a face of the first planar intermedialbinding layer to a face of the second planar intermedial binding layerwith the matrices of void cells extending away from the planarintermedial binding layers. In one implementations, the bondingoperation 1715 results in a single intermedial binding layer linking thefirst matrix of void cells and the second matrix of void cells together.In another implementation, the bonding operation 1715 periodically tackwelds the intermedial binding layers together resulting in two distinctbinding layers fixedly attached together. Periodically bonding theintermedial binding layers together may leave fluid passageways betweenthe void cells lying between the intermedial binding layers.

Further, the first and second intermedial binding layers may belaminated together such that openings in opposing void cells in thefirst half and second half of the cellular cushioning system meet oneanother. Alternatively, the first half and second half of the cellularcushioning system may be manufactured in one step using any knownmanufacturing techniques. Further yet, the first half and second half ofthe cellular cushioning system may be manufactured using techniquesother than molding (e.g., vacuum forming, pressure forming, andextruding).

In implementations utilizing a pixilated layer, an optional moldingoperation 1720 molds the pixilated layer for the cellular cushioningsystem. The pixilated layer is generally planar with a series ofchannels that frame areas of the pixilated layer generally correspondingto the sizes and positions of individual void cells in the first and/orsecond matrices of void cells. The pixilated layer is further configuredwith a thickness, stiffness, channel depth, channel width to achieve adesired degree of independent compression of the individual void cells.If the pixilated layer is utilized, optional attaching operation 1725attaches the pixilated layer to an outer surface of either the first orthe second matrices of void cells oriented generally parallel to theplanar intermedial binding layer. The pixilated layer may be attached bybeing glued, welded, or using any other attachment methods. Further, twopixilated layers may be used, one attached to the first matrix of voidcells and a second attached to the second matrix of void cells.

A decision operation 1727 decides if the cellular cushioning systemneeds additional layers of void cells bound together with a bindinglayer. If yes, operations 1705 through 1727 are repeated. If no,attaching operation 1729 attaches the multiple layers of the cellularcushioning system together. If there is only one layer of the cellularcushioning system, operation 1729 is inapplicable.

A compressing operation 1730 compresses one or more of the void cellswithin an independent compression range without significantlycompressing one or more adjacent void cells. Adjacent void cells includeone or more of neighboring void cells, opposing void cells, and neighboropposing void cells. In one implementation, the neighboring void cellsare fluidly connected by dedicated passages or merely gaps between thefirst and second intermedial binding layers. This allows the air orother fluid within the compressed void cell to enter and exit the voidcell.

The independent compression range is the displacement range of thecompressed void cell that does not significantly compress adjacent voidcells. The void cell is compressed in a general direction substantiallynormal to the intermedial binding layers. If the void cell is compressedbeyond the independent compression range, the intermedial binding layerswill be deflected and/or the void cells adjacent the compressed voidcell will be compressed. In one implementation, even after theindependent compression displacement is exceeded, the void cellsadjacent the compressed void cell are compressed significantly less thanthe compressed void cell itself. Further, multiple void cells may becompressed in compressing operation 1725.

A de-compressing operation 1735 de-compresses one or more compressedvoid cells without substantially de-compressing at least one adjacentcompressed void cell, so long as the de-compressed void cell is withinits independent compression range. If the de-compressed void cell isoutside its independent compression range, adjacent void cells will alsode-compress until the de-compressed void cell returns within itsindependent compression range. If the de-compressed void cell isde-compressed to a zero load, the cellular cushioning system will returnto its original state. In other implementations, the cellular cushioningsystem may be permanently deformed (e.g., in a one-time use cellularcushioning system).

The above specification, examples, and data provide a completedescription of the structure and use of exemplary embodiments of theinvention. Since many embodiments of the invention can be made withoutdeparting from the spirit and scope of the invention, the inventionresides in the claims hereinafter appended. Furthermore, structuralfeatures of the different embodiments may be combined in yet otherembodiments without departing from the recited claims.

What is claimed is:
 1. A method comprising: applying a cushioningmaterial to a curved surface, the material comprising a first matrix ofvoid cells opposing a second matrix of void cells, wherein at least twoof the void cells in the first matrix are coupled to at least two of thevoid cells in the second matrix via an intermedial binding layer and ateach void cell of the first matrix and the second matrix includes anopening in continuous fluid communication with an environment externalto the cushioning material.
 2. The method of claim 1, furthercomprising: compressing a void cell in the first matrix within anindependent compression range of the cushioning material and in adirection substantially normal to the intermedial binding layer withoutsubstantially compressing at least one neighboring void cell in thefirst matrix and at least one opposing void cell in the second matrix ofvoid cells.
 3. The method of claim 2, further comprising: compressingthe void cell outside the independent compression range to deflect theintermedial binding layer and compress the opposing void cell in thesecond matrix of void cells.
 4. The method of claim 3, whereincompressing the void cell outside the independent compression rangerequires greater force than compressing the void cell within theindependent compression range.
 5. The method of claim 2, wherein eachvoid cell in the first matrix of void cells has a substantially equalresistance to deformation at all deformation magnitudes within theindependent compression range.
 6. The method of claim 1, wherein eachvoid cell in the first matrix of void cells has an increased resistanceto deformation with increased deformation magnitude outside theindependent compression range.
 7. The method of claim 1, wherein thevoid cells in the first matrix have a higher resistance to deflectionthan the void cells in the second matrix.
 8. A cushioning materialcomprising: a first matrix of void cells; a second matrix of void cellsopposing the first matrix of void cells, each void cell of the firstmatrix and the second matrix including an opening in continuous fluidcommunication with an environment external to the cushioning material;and an intermedial binding layer coupling at least two of the void cellsin the first matrix to at least two of the void cells in the secondmatrix.
 9. The cushioning material of claim 8, wherein the cushioningmaterial conforms to a curved surface of an adjacent object.
 10. Thecushioning material of claim 8, wherein each of the void cells in thefirst matrix have an open face that faces an open face of each of thevoid cells in the second matrix, wherein the open faces in the firstmatrix generally align with the open faces in the second matrix.
 11. Thecushioning material of claim 8, wherein compression of a void cellwithin the first matrix in a direction substantially normal to theintermedial binding layer occurs without substantial deflection of atleast one neighboring void cell in the first matrix and at least oneopposing void cell in the second matrix.
 12. The cushioning material ofclaim 11, wherein de-compression of the void cell occurs withoutde-compression of the neighboring void cell.
 13. The cushioning materialof claim 11, wherein compression and compression of the void celloutside of an independent compression range of the cushioning materialdeflects the intermedial binding layer and compresses the at least oneadjacent void cell.
 14. The cushioning material of claim 13, whereincompression of the void cell outside the independent compression rangerequires greater force than compression of the void cell within theindependent compression range.
 15. The cushioning material of claim 8,wherein the intermedial binding layer has an opening where each voidcell meets the intermedial binding layer.
 16. The cushioning material ofclaim 8, wherein the intermedial binding layer includes a first halfthat couples the first matrix of void cells together and a second halfthat couples the second matrix of void cells together, and wherein thefirst half and the second half are attached together.
 17. The cushioningmaterial of claim 8, wherein the first half and the second half areattached together using periodic spot welds of the first half to thesecond half.
 18. A method of manufacturing a cellular cushioning systemcomprising: molding a first matrix of void cells open toward andinterconnected by a first intermedial binding layer; molding a secondmatrix of void cells open toward and interconnected by a secondintermedial binding layer, each void cell in the first matrix and thesecond matrix including an opening in continuous fluid communicationwith an environment external to the cellular cushioning system; andwelding the first and the second intermedial binding layers together sothat openings in the void cells of the first matrix and the secondmatrix face one another.
 19. The method of claim 18, further comprising:molding a pixilated layer; and attaching the pixilated layer to an outersurface of each void cell of the first matrix of void cells.
 20. Themethod of claim 19, further comprising: compressing a void cell in thefirst matrix in a direction substantially normal to the firstintermedial binding layer without substantial deflection of at least oneneighboring void cell in the first matrix and at least one opposing voidcell in the second matrix.